Diffusors in small booth and control room

[mixaudio]

Hello everyone, and thanks in advance for your invaluable help.

My room dimensions are:

- Vocal booth: 8' 6" x 6' x 8'

- Control room: 14' x 12' 4" x 8". Distance from back wall to engineer's chair is 7' to 8'

On the shown screenshot I'm contemplating 4" thick bass traps on some of the corners and all other panels would be 2" for broadband absorption. Floor is laminated wood in both rooms.

Questions:

1- Given the dimensions of both rooms, would diffusion be desirable for good acoustics? Or just the bass traps and broadband panels would do fine?

2- If adding diffuser(s) is suggested, would you think the suggested placement shown on the screenshots is a good idea on both the vocal booth and control room? Also, would those glass block windows have a bad acoustic effect or interaction with the diffusers on the sides? The depth of those glass blocks is about 2" and they are 8" wide.

3- Considering these rooms dimensions and distance from engineer's chair to the back wall, which numbers (or frequencies) should I be looking for or entering when calculating the diffuser well depths and widths? Also is there a version of the acoustics calculator for Mac? The one I've seen posted around here seems to be for Windows.

4- Given the space available, it seems like I could make them 3.5' tall. Would that be good? The booth would have 2 stacked.

5- Are these supposed to be filled inside with fiber or something else?

6- For the vocal booth, what difference would it make using "skyline" diffusers instead of quadratic? I hope I'm using the terms correctly. It just seems form other threads I've seen that the ones with the long grooves are called "quadratic" and the ones with the small wood pieces "skyline".

7- For the control room, should I consider 2 more in place of the broadband panels shown now to the sides of the diffusors?

I'm sure I'll run into other questions sooner or later, but for now your input on these 7 questions would be of great value and highly appreciated!

Thanks!

Rodolfo F.

I hope the screenshots show the idea clearly…

[Glenn Kuras]

1- Given the dimensions of both rooms, would diffusion be desirable for good acoustics? Or just the bass traps and broadband panels would do fine?

For the control room it would be fine. See the following to give you some ideas on diffusion set up. GIK Acoustics: Room Setup

For the smaller room I would not make it the main focus. Start with bass trapping the 2" panels for flutter echo. At that point put the diffusion on any bare walls if you would like. Honestly in a room that small I myself would not use diffusion as you will never get the the full benefit of it.
See the following to understand how diffusion works. How Diffusion Really Works. Spotlight on MASSIVE Mastering.

2- If adding diffusor(s) is suggested, would you think the suggested placement shown on the screenshots is a good idea on both the vocal booth and control room? Also, would those glass block windows have a bad acoustic effect or interaction with the diffusors on the sides? The depth of those glass blocks is about 2" and they are 8" wide.

Control room-The back wall is fine but I still would put thick absorption right behind you with diffusion around that.
Vocal booth- Once again I would not use it, but if you do get the diffusion as far away from the mic as possible, unless you are looking for a "effect" from time to time.

3- Considering these rooms dimensions and distance from engineer's chair to the back wall, which numbers (or frequencies) should I be looking for or entering when calculating the diffusor well depths and widths? Also is there a version of the acoustics calculator for Mac? The one I've seen posted around here seems to be for Windows.

5" or more thick is general rule for depth.

5- Are these supposed to be filled inside with fiber or something else?

You could do that to help with a bit of low end control, but don't mistaken it for it being some kind of bass trap.

[G. E.]

Originally Posted by mixaudio

... 6- For the vocal booth, what difference would it make using "skyline" diffusers instead of quadratic? I hope I'm using the terms correctly. It just seems form other threads I've seen that the ones with the long grooves are called "quadratic" and the ones with the small wood pieces "skyline". ...

Talking about diffusors "skyline" means it's about a two-dimensional (2D) diffusor opposed to a one-dimensional (1D) whereas "quadratic" says something about how the well depths are calculated (that is using quadratic residues in the formula). You see there may even be a diffusor that is both "skyline" AND "quadratic"!

In the back most often we see 1D-diffusors based on quadratic residues (1D-QRD) whereas for example on the ceiling its definitly more appropriate to use 2D-diffusors (since usually there is no preferred direction). For my part I went with a couple of 2D-diffusors based on the primitive root theory for both walls and ceiling.

[mixaudio]

Thanks a lot Glenn for your response!

For the control room it would be fine. See the following to give you some ideas on diffusion set up.

Wow, I notice that that compared to your graphics, my sketch shows many more absorptive panels. I've been re-arranging my 2" wall panels to avoid having too many.

By the way, I've been calling the 2" panels "broadband" and the 4" corner panels "bass trap" but I'm not sure that this is correct. Does that have to do with whether or not the 2" panels are spaced from the wall? In other words, would it be that by spacing a 2" panel, it would work more with bass freqs and by leaving no space it would work more as broadband?


By looking at the amount of 4" panels on the corners on these screenshots, would I still need to install the 2" ones spaced from the walls? Does that look like too many still?? Is there a way to determine how many 2" broadband panels to use on the walls, and how many 4" bass traps on the corners?

Showing only the 4" panels on corners:

Showing only the 2" panels on walls:

Showing all panels:


Since I'd have wood floor, I thought of adding a few 2" ceiling panels. Would these be necessary? Are 3 too many? How about the angle I'm suggesting on the screenshot? I like how that looks better, but would it be preferable to not angle them?



What about the 2" panels behind the monitors? Is there too much of a difference if those are horizontal or vertical like shown here?

For the smaller room I would not make it the main focus. Start with bass trapping the 2" panels for flutter echo.

Does that mean separating the 2" panels by 2" from the wall? I'm a bit confused as I find many forum users considering the 4" panels to be the ones working with bass freqs and the 2" ones working more like broadband.

Control room-The back wall is fine but I still would put thick absorption right behind you with diffusion around that.

I apologize if there is some redundancy on some of my questions. There are 2 angled 4" panels placed on the corner where the back wall and ceiling meet. So, besides those being 4", should I also boost those 2" panels on the sides of the diffusers to become 4"?

Thanks again for your invaluable help!

Rodolfo F.

[mixaudio]

Originally Posted by G. E.

Talking about diffusors "skyline" means it's about a two-dimensional (2D) diffusor opposed to a one-dimensional (1D) whereas "quadratic" says something about how the well depths are calculated (that is using quadratic residues in the formula). You see there may even be a diffusor that is both "skyline" AND "quadratic"!

In the back most often we see 1D-diffusors based on quadratic residues (1D-QRD) whereas for example on the ceiling its definitly more appropriate to use 2D-diffusors (since usually there is no preferred direction). For my part I went with a couple of 2D-diffusors based on the primitive root theory for both walls and ceiling.

Hey Gernot, thanks for that info! That clarifies which is which…

Rodolfo F.